The present invention relates to a new and improved construction of apparatus for use during continuous casting for the introduction of a liquid melt, typically a steel melt, into the casting head of a mold, which apparatus comprises a tubular-shaped portion which directly connects with a casting or pouring vessel, the cross-sectional area of the tubular-shaped portion being greater than the cross-sectional area of the pouring outlet provided at the casting vessel, and there is further provided a chamber-like portion of greater cross-sectional area which merges with the tubular-shaped portion.
There is known in this particular field of technology a tubular infeed or delivery device which possesses a vessel-like widened portion at the side of the tubular portion which confronts the mold, this widened portion possessing one or a number of outlet openings, the cross-section of which is considerably smaller than the cross-section of the tubular portion. However, this prior art piece of equipment is only intended to solve the problem concerning the formation of turbulence through nozzle-like outlet openings. The tubular portion or tube is accommodated to the cross-section of the casting jet.
Furthermore, apparatus is known in this art wherein for the purpose of distributing a melt, a chamber merges with a tubular-shaped portion which is mounted at a tundish. This chamber immerses into the liquid melt in the mold and possesses outlet openings having cross-sections which are larger than the cross-section of the tubular-shaped portion. The purpose of this piece of equipment is to reduce the number and size of the disturbing contaminants at the casting by virtue of a reduction in the penetration depth of the casting jet.
These devices, which have become known in this particular art under the terminology casting boxes, are however associated with a decisive drawback. Due to the size and construction of the outlet openings, there prevails an unstable flow at the outflowing steel. This causes an uncontrolled, non-symmetrical efflux or discharge, so that the growth of the strand shell or skin at the narrow sides is differently affected or in fact there can be ascertained erosion effects. Further, there is impaired the effectiveness of the separation of contaminants.